1. Field of the Invention
The present invention relates to a wireless power transmitting device.
2. Related Art
Recently, wireless power transmitting devices of an electromagnetic induction type for mobile devices are spreading. Power is wirelessly transmitted to a power receiving coil built in a power receiver such as an electronic device through an alternate current magnetic field produced by a power transmitting coil built in the wireless power transmitting device. The power transmitted to the power receiving coil is supplied to a load such as a secondary battery through a rectifying circuit. The secondary battery in the power receiver can be charged conveniently by just placing the power receiver on the wireless power transmitting device, and a power connector does not need to be inserted and removed, so that there is an advantage that a waterproof function and a dust-proof function can be added to the power receiver.
Wireless power transmitting devices are demanded to improve efficiency of power transmission from power transmitting coils to power receiving coils. Hence, it is necessary to accurately align a position of a power receiving coil to a position of a power transmitting coil. As one of these means for realizing this alignment, there is a method of detecting a position of the power receiving coil and moving a power transmitting coil close to the power receiving coil by means of a moving mechanism provided in a wireless power transmitting device (see, for example, Japanese Patent Application Laid-Open No. 2010-263663).